The present invention, in some embodiments thereof, relates to image analysis and, more particularly, but not exclusively, to a method and system for cephalometric analysis.
Medical practitioners, such as orthodontists, maxillofacial surgeons, ear, nose and throat surgeons, and other physicians use cephalometry for diagnosis, prognosis and treatment planning. Cephalometric analysis allows defining certain norms and anomalies of a skeletal, dental and soft tissue of the craniofacial complex. Cephalometric measures of individuals can be compared with norms for age, sex and population group. Generally, cephalometric analysis includes identification of specific landmarks on a roentgenogram (an X-ray image) of the head. By plotting lines on the image, and measuring various measures of these lines the medical practitioner evaluates growth and development of anatomic structures. A comparison of the measures to previously acquired control group measures (e.g., normal populations of similar age, gender and ethnic group) allows the practitioner to diagnose bony and soft tissue anatomical variants and anomalies.
Cephalometric analysis has also been proposed as a tool for diagnosing sleep-disordered breathing (SDB) [Finkelstein et al., “Frontal and lateral cephalometry in patients with sleep-disordered breathing,” The Laryngoscope 111, 4:623-641 (2001)]. Lateral and frontal cephalometric radiographs were analyzed in a series of normal patients and those with varying degrees of SDB, and the degrees of narrowing or other unfavorable anatomical changes that may differentiate SDB subjects from normal subjects. SDB was found to be associated with statistically significant changes in several cephalometric measurements.
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